TW548794B - Method of forming barrier layer between low k material layer and interconnect - Google Patents

Abstract

This invention discloses a method of forming barrier layer between low k material layer and interconnect. Firstly, a substrate is provided, which is covered with an insulation layer and has a metal interconnect formed therein. Then, a sealing layer is formed on the metal interconnect and on top of the dielectric layer. Subsequently, a reaction gas is used to perform a plasma treatment on the sealing layer, in which the reaction gas used includes at least one of CO2, NH3, NO2, silane, 3MS and 4MS. Finally, a low k material is formed on the sealing layer.

Description

Correction and replacement on February 14, 103 Page IX. Description of the invention: ---- Field of the invention: In particular, it relates to a method for manufacturing a semiconductor device in the present invention, forming a transition between thin wires of a layer of low dielectric material. Layer method. Relevant technical description: With the development of integrated materials, copper metal with low residual constant and high electron migration resistance has been woven into wire as a metal interconnect, replacing traditional metal processing technology. Since the resistivity of copper is lower than that of Shaw, it will have a higher signal transmission speed under a fixed line width. Although the physical properties of copper have great advantages for application to components, steel has some disadvantages that must not be overcome. For example, noodles are very susceptible to oxidation during the manufacturing process. In addition, copper can easily diffuse into adjacent materials (including dielectrics), so when copper is used as the metal interconnect, it is necessary to seal the copper wire with a barrier material. Traditionally, a metal barrier material is generally deposited after the copper metal is deposited, which is generally referred to as a sealing layer, a cap layer, or an encapsulation layer. Although other materials can also be used, it is usually covered with nitride. FIG. 1 is a cross-sectional view of a conventional dual-mosaic wire. Reference numeral 100 denotes a semiconductor substrate, which is covered with an insulating layer 102 and has a plurality of trenches. The steel metal layer 104 is deposited on the insulating layer 102 and filled in the trench. The excess copper metal layer 104 is usually replaced by 548794 on February 14, 103. The surface of the insulating layer 102 is usually removed by chemical mechanical polishing. After that, a cap layer 106 is deposited on the copper metal layer ι04 and the insulating layer 102. A low-k material layer 108 having a dual damascene structure is then formed on the capping layer 106. Similarly, a copper metal layer 110 is deposited on the low dielectric constant material layer 108 and filled into the dual damascene structure. Here, the copper metal layer 110 in the 'dual damascene structure is electrically connected to the copper interconnect 104 via the ® capping layer 106 which is removed, as shown in FIG. 1. The excess copper metal layer 110 is also removed by chemical mechanical polishing (chemicai mechanicai) to a low dielectric constant material layer 108. The capping layer 106 is usually silicon nitride (SiN) as a metal barrier This layer prevents the copper atoms in the copper metal layers 104 and 110 from diffusing into the insulating layer 102 and the low-dielectric constant material layer 108. In addition, the capping layer 106 can also be used as a final termination layer in a dual damascene process. However, there is a problem with the reliability of the capping layer between the low dielectric constant drain layer and the connection, such as the electron migration between copper wires (other peaks such as 〇11, _ and dependent dielectric breakdown, TDDB). And Lu, after the capping layer is deposited on the steel surface, then the dielectric layer will be deposited on the capping layer. This process of depositing the dielectric layer will cause stress to damage the capping layer. After the dual damascene process_ In the chemical mechanical research process, the low dielectric constant material layer and the capping layer 6 February 14, 103 Correction of poor adhesion between replacement pages will cause the dielectric layer to peel off, leading to the entry of water vapor and copper atoms Summary of the Invention: In light of this, this The purpose of the invention is to provide a method for forming a barrier layer between a low-dielectric material layer and an interconnect, by applying a plasma treatment to the capping layer to increase the distance between the low-W electric constant material layer and the capping layer. Another object of the present invention is to provide a method for forming a barrier layer between a low-dielectric material layer and an interconnect, by forming a barrier layer between the low-dielectric constant material layer and the capping layer. An adhesion layer is used to prevent the capping layer from being damaged during the formation of the low-dielectric material layer, and to prevent the low-dielectric material layer from being peeled off in the subsequent chemical mechanical polishing process. According to the above object, the present invention provides an A method for forming a barrier layer between a dielectric material layer and an interconnect. First, a substrate is provided, which is covered with an insulating layer and the insulating layer has a metal interconnect. Then, a metal interconnect and an insulating layer are formed over the substrate. One cover is wide. Then, the cover layer is subjected to a plasma treatment with a reaction gas, which includes carbon dioxide, ammonia, nitrogen dioxide, silane, trimethylsilane (3MS) and Methyl silicon At least one kind of alkane (4MS). Finally, a low-dielectric material layer is formed on the capping layer. Furthermore, the capping layer is composed of nitride nitride, silicon carbide, hydrocarbon, silicon oxycarbide, and carbon. According to another object of the present invention, the present invention provides a method for forming a barrier layer between a low dielectric material layer and an interconnect. First, a substrate is provided, which is covered with an insulating layer and

Claims (1)

548794. ------ · 'February 14, 2013 Correction Replacement page can be one of Silicon Carbide (SiC), Silicon Carbide (SICH), Silicon Carbide (SiCO), and Silicon Carbide (SiCN) Made up. After that, referring to FIG. 2C, a plasma treatment is performed on the capping layer 206. Among them, the reaction gases used are carbon dioxide (C0 2), ammonia _ 3), nitrogen dioxide (NO 2), Shi Xiyan (SiH 4), trimethyl group (trimethylSilane (3MS)) and At least one kind of tetramethylsilane (4MS) to form a capping layer 206a having a surface activation. In the reaction gas passed in this embodiment, the flow rates of carbon dioxide, ammonia, nitrogen dioxide, silane, trimethylsilane (3MS) and tetramethylsilane (4MS) are in the range of 500 to 1500 SCCm, and 1500 to 3500SCCm range, 500 to 1500SCCm range, 500 to 1500SCCm range, 500 to 2500SCCm range, and 500 to 2500SCCm range. Next, please refer to FIG. 2d. A low-dielectric (10wk) material layer 208, such as SILK, FLARE, and PAII, is formed on the capping layer 206a. The low-dielectric material layer 208 has a double damascene structure. Subsequently, the copper metal layer 21 is deposited on the low-dielectric material layer 208 and filled into the dual damascene structure. Here, the copper metal layer 21 in the dual damascene structure is electrically connected to the copper interconnect 204 through the capping layer 206a of the removed portion. ^ Next, referring to FIG. 2e, the extra copper metal layer 21 is borrowed. The surface of the low-dielectric material layer 208 is ground by a chemical mechanical polishing method to form a copper interconnect 210 in the low-dielectric material layer 2 () 8. 9 February 14, 103 Correction Replacement * page as mentioned earlier 'Capping layer 206 & acts as a metal barrier layer to prevent copper atoms in copper metals 204 and 210 from diffusing into insulating layer 2 () 2 and lower The dielectric constant material layer can be used as a meal-engraving stop layer in the double-wire setting process. Due to the action of the cap layer 206a having a surface activation and the low dielectric material layer 208, the low dielectric constant material layer 208 and the cap layer 206a are improved. Therefore, according to the method of the present invention, the dielectric constant material layer 208 can be prevented from being relayed in the subsequent chemical mechanical process. That is, the problem of lowered reliability due to the good adhesion between the capping layer and the low dielectric material layer can be eliminated. The method of forming a barrier layer between the low-dielectric material layer and the interconnects according to the second embodiment of the present invention will be described with reference to FIGS. 3a to 3d. First, referring to FIG. 3a, a substrate 200 is provided. Next, an insulating layer 202, such as a stone oxide layer or an organosilicate glass (OSG), is deposited on the substrate 200. In this insulating layer 202, a trench for forming interconnects is formed. Then, a metal layer 204, such as copper metal, is deposited on the insulating layer 202 and filled into the trench. The extra copper metal layer 204 is ground to the surface of the insulating layer 202 by a chemical mechanical polishing method to form a copper interconnect 204 in the insulating layer 202. Next, referring to FIG. 3b, a capping layer 206 is then formed on the copper interconnects 204 and the insulating layer 202. In this embodiment, the capping layer 206 is a nitrided silicon nitride layer, which may also be composed of silicon carbide (SiC), silicon carbide (SiCH), silicon oxycarbide (sic0), and silicon carbonitride (SlCN). One kind of composition. Thereafter, an adhesion layer .207 is formed on the capping layer 206. 548794. < February 14, 103, Replacement page correction In this embodiment, there are two methods of forming this adhesion layer 207. One is to use chemical vapor deposition to form an adhesion layer 207. The reaction gases used are carbon dioxide, ammonia, nitrogen dioxide, silane, trimethylsilicon (3MS), and tetramethyl At least one kind of silane (4MS); the other is to apply a silicate solution (as an adhesion promoter) on the capping layer 206 to form an adhesion layer 207. Among them, the thickness of the adhesion layer 207 formed by using a chemical vapor deposition method is in a range of 100 to 2000 angstroms. In addition, the thickness of the adhesion layer 207 formed by applying a silicate solution is in the range of 1000 to 2000 angstroms. Next, referring to FIG. 3C, a low-k material layer 208 such as SILK, FLARE, and PAI1 'is formed on the adhesion layer 207. The low-dielectric material layer 208 has a double damascene structure. Subsequently, the copper metal layer 21 is deposited on the low-dielectric material layer and filled into the dual damascene structure. Here, the copper metal layer 210 in the 'dual damascene structure is electrically connected to the copper interconnect 204 via the removed adhesive layer 207 and the capping layer 206 thereunder. · Next, referring to Fig. 3d, the excess copper metal layer 210 is ground to the surface of the low-dielectric material layer 208 by chemical mechanical polishing to form a copper interconnect 210 in the low-dielectric material layer 2⑽. In this embodiment, the adhesion layer 2007 and the capping layer 2 () 6 below it constitute a composite barrier layer 'and can increase the adhesion between the adhesion layer 2 and the low-dielectric material layer 208. that is,